ipad version of Storyist won't open on Air

Recently upgraded from ipad 2 to an air. Storyist was saved to cloud. Tried to use last night, won't open. Error message: cocoa error 260.
have upated ios on both the 2 and the air. the 2 opens and shows all projects.....any ideas? couldn't any newer versions of ipad apps? only have ipad....grrrrr upgraded my ipad for more storage, better display etc...does this mean I have to continue writing on my 2?